Ulvac EGL-206M, Instruction Manual

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SECTION 3
13
3.3 Safeguards against X-Rays (See Fig. 3-5.)
Although this electron beam gun is energized with a relatively low voltage of
10 kVDC, long wavelength X-rays are emitted from the hearth bombarded
with electron beams. If the vacuum chamber is made of metal, most X-rays
are absorbed by the metal, but a small dose of X-rays may leak defending on
the thickness of the gasket. X-rays can be harmful to the human body if
exposed for a long time. For safety, ULVAC recommends the following
methods.
View port glass
Use Pyrex glass inside and lead glass (8 mm thick) outside for the window.
Gasket section
Patch a 0.8 to 1.0 mm thick SUS304 sheet inside or outside the gasket.
After this treatment, measure the dose of X-rays with the electron beam gun
in operation, and make sure that it is well below the internationally approved
tolerance.